The study of the two proteoglycans isolated from extracts of pig skin will be continued by a more detailed examination of the structure and behavior of the proteodermatan sulfate. The iduronic acid content of the dermatan sulfate chains will be determined, and the sequence of the neutral sugars and the glucosamine in the oligosaccharide chains will be worked out. The molecular weight of the intact proteoglycan will be measured by sedimentation equilibrium, and observations will be made on the possible binding or interaction with collagen of skin.